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51.
Information systems (IS) facilitate organisations to increase responsiveness and reduce the costs of their supply chain. This paper seeks to make a contribution through exploring and visualising knowledge mapping from the perspective of IS investment evaluation. The evaluation of IS is regarded as a challenging and complex process, which becomes even more difficult with the increased complexity of IS. The intricacy of IS evaluation, however, is due to numerous interrelated factors (e.g. costs, benefits and risks) that have human or organisational dimensions. With this in mind, there appears to be an increasing need to assess investment decision-making processes, to better understand the often far-reaching implications associated with technology adoption and interrelated knowledge components (KC). Through the identification and extrapolation of key learning issues from the literature and empirical findings, organisations can better improve their business processes and thereby their effectiveness and efficiency, while preventing others from making costly oversights that may not necessarily be only financial. In seeking to enlighten the often obscure evaluation of IS investments, this paper attempts to inductively emphasise the dissemination of knowledge and learning through the application of a fuzzy Expert System (ES) based knowledge mapping technique (i.e. Fuzzy Cognitive Map [FCM]). The rationale for exploring knowledge and IS investment evaluation is that a knowledge map will materialise for others to exploit during their specific technology evaluation. This is realised through conceptualising the explicit and tacit investment drivers. Among the several findings drawn from this research, the key resulting knowledge mapping through FCM demonstrated the complex, multifaceted and emergent behaviour of causal relationships within the knowledge area. The principal relationships and knowledge within IS investment evaluation are illustrated as being determined by a blend of managerial and user perspectives.  相似文献   
52.
On the Predominant Electron-Donicity of Polar Solid Surfaces   总被引:2,自引:0,他引:2  
The reasons for the predominant electron-donicity of almost all solid polar surfaces and its implications are discussed in this paper. By contact angle or interfacial tension measurements, the electron-accepting as well as the electron-donating properties of polar liquids can be ascertained, through the interplay between their energies of adhesion and cohesion. For the solid-liquid interface, direct interfacial tension measurements are not possible, but indirectly, solid/liquid interfacial tensions of polar systems can be obtained by contact angle measurement. However, as the energy of cohesion of a solid does not influence the contact angle formed by a liquid drop placed upon its surface, one can only measure the solid surface'ks residual polar property, manifested by the energy of adhesion between solid and liquid. This residual polar property is of necessity the dominant component; in most cases this turns out to be its electron donicity. When, by means of contact angle measurements with polar liquids, both electron-accepting and electron-donating potentials are found on a polar solid, it is most likely still partly covered with a polar liquid: usually water. The amount of residual water of hydration of a polar solid follows from its polar (Lewis acid-base) surface tension component (γAB). The degree of orientation of the residual water of hydration on a polar solid can be expressed by the ratio of the electron-donating to electron-accepting potentials (γ), measured on the hydrated surface.  相似文献   
53.
讨论了锌系工件喷涂的相关工艺、现场管理、技术参数、质量检验和环境要求等。  相似文献   
54.
不同地区不同等级复烤烟叶中重要致香物质的分析比较   总被引:4,自引:1,他引:4  
本文采用同时蒸馏萃取(SDE)/气相色谱/质谱联用法(GC/MS)对相同品种、不同地区、不同等级复烤烟叶中的重要致香物质进行分析比较;并且对同时蒸馏萃取法进行重复性和回收率试验。结果表明相同品种、不同地区、不同等级复烤烟叶中重要致香物质的含量差别较大;同时蒸馏萃取法具有良好的重复性和较高的回收率。  相似文献   
55.
ExPosition is a new comprehensive R package providing crisp graphics and implementing multivariate analysis methods based on the singular value decomposition (svd). The core techniques implemented in ExPosition are: principal components analysis, (metric) multidimensional scaling, correspondence analysis, and several of their recent extensions such as barycentric discriminant analyses (e.g., discriminant correspondence analysis), multi-table analyses (e.g.,multiple factor analysis, Statis, and distatis), and non-parametric resampling techniques (e.g., permutation and bootstrap). Several examples highlight the major differences between ExPosition and similar packages. Finally, the future directions of ExPosition are discussed.  相似文献   
56.
A new model to predict the adsorption equilibrium of mixtures containing supercritical components was presented. The difference in the adsorption mechanism between the supercritical components and the condensable components was accounted for in the new model. Lateral interaction in the adsorbed phase was also considered in the local isotherm. The new model was verified by the experimental data of the mixture CH4/CO2/C2H6 on activated carbon JX101 collected for 283-313 K and pressures up to . It was also verified with the experimental data published previously in literature. Considerable improvement in the prediction precision was achieved in using the new model to predict the adsorption of mixtures on activated carbon.  相似文献   
57.
陈化过程中不同部位烤烟烟叶香味成分变化的研究   总被引:1,自引:0,他引:1  
采用SDE-GC/MS法对陈化过程中不同部位烤烟烟叶的香味成分进行分析检测,并按照香味物质的产生来源对分析结果进行了分类研究。结果表明,陈化过程中不同部位烟叶的香味物质的变化情况差别明显。从香味成分的变化情况看,各个部位适宜的陈化时间有所不同:上部烟叶2年以上,中部烟叶1.5~2年,下部烟叶1年左右。  相似文献   
58.
恒粘天然橡胶理化性能的研究   总被引:2,自引:0,他引:2  
用粘度稳定剂处理天然橡胶鲜胶乳和湿杂胶,研究了粘度稳定剂种类及处理方法对橡胶的P0、PRI、MV、氮含量和加速贮存硬化值(△P)等的影响。结果表明,鲜胶乳所制得的恒粘胶经加速贮存后的△P≤1个塑性值,门尼粘度值变化量(△MV)≤3个门尼值。其它性能虽有变化,但均能达到天然生胶标准的要求。自然凝固制得的恒粘胶的P0、PRI和MV相对较高,氮含量相对较低。粘度稳定剂延长了鲜胶乳的凝固时间。粘度稳定剂处理后的杂胶,△P和△MV减少,但恒粘效果不及鲜胶乳制得的恒粘胶。  相似文献   
59.
提出了一种新的简单有效的融合多颜色分量的分割方法,首先在六个不同的颜色空间中选择最佳的待分割颜色分量,然后应用直方图和空间模糊C均值(SFCM)技术对不同颜色分量进行自适应初始分割,最后融合分割结果并进行区域合并。利用该算法在Berkeley图像库上进行了大量实验,实验结果表明,与当前一些经典分割算法Mean-shift、FCR、CTM等相比,利用该方法能够获得更好的分割结果以及更优的性能指标。  相似文献   
60.
热解气化过程中 ,促进焦油的裂解使之转化为高热值煤气 ,对高挥发分劣质煤和生物质燃料的清洁高效利用具有重要的意义 .在固定床反应器上 ,以石英砂和两种烟煤在循环流化床锅炉上燃烧形成的循环灰为床料 ,实验研究了焦油中含量较高的 1 -甲基萘的裂解反应 ,测定了反应动力学参数 .结果表明 ,与石英砂条件下相比 ,循环灰促进了 1 -甲基萘的裂解 ,反应活化能降低 ,裂解气体的总产率提高  相似文献   
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